Nowadays mostly everyone has the new iphone or Samsung Galaxy. There is normally no need to buy a mobile phone if you already have one. In China the phone and SIM card are bought separately and therefore you can simply buy a SIM card when you arrive. These normally come with the same value of credit as you pay for the card so effectively don’t cost you anything. For topping up you can buy a card on campus for 50 and 100 RMB. You can join the campus cornet cluster which has approximately 18,000 users among our teachers and students, 5rmb/month.